2018 Atlantic hurricane season (Cooper)
The 2018 Atlantic hurricane season '''was an active, deadly, and destructive Atlantic hurricane season, although much less so than the previous season. It featured a total of 15 named storms, 8 hurricanes, and 4 major hurricanes. The season officially began on June 1 and ended on November 30. These dates historically describe the period of year when most tropical cyclones form in the Atlantic basin. However, the season's first storm, Alberto, formed on May 31, a day before the season officially began. The final storm, Oscar, transitioned to a post-tropical cyclone on November 13. Following Alberto, Tropical Storm Beryl brought heavy rainfall and flooding to the Southeastern United States. In early July, Tropical Storm Chris caused flooding and mudslides in the Leeward Islands. In late September, Hurricane Leslie caused widespread devastation in Cuba and Hispaniola, mainly by rainfall-triggered flooding and mudslides, and later affected the New England area as a strong tropical storm. With 403 fatalities attributed to it, Leslie was the deadliest storm of the season. The season's costliest storm was Hurricane Gordon, a large Category 4 hurricane that left $31.6 billion (USD) in damages and 129 fatalities across the Greater Antilles and United States. The strongest storm was Hurricane Isaac, a powerful and long-lived Category 4 hurricane that threatened the Lesser Antilles, who were still recovering from Hurricane Irma a year prior. Initial predictions for the season were divided, although most forecasting groups were forecasting near-average activity by the time the season began. However, activity surpassed the predictions. Seasonal forecasts Ahead of and during the season, several national meteorological services and scientific agencies forecast how many named storms, hurricanes and major (Category 3 or higher on the Saffir-Simpson scale) hurricanes will form during a season and/or how many tropical cyclones will affect a particular country. These agencies include the Tropical Storm Risk (TSR) Consortium of the University College London, the National Oceanic and Atmospheric Administration (NOAA) and the Colorado State University (CSU). The forecasts include weekly and monthly changes in significant factors that help determine the number of tropical storms, hurricanes, and major hurricanes within a particular year. Some of these forecasts also take into consideration what happened in previous seasons and an ongoing La Niña event that had recently formed in November 2017. On average, an Atlantic hurricane season between 1981 and 2010 contained twelve tropical storms, six hurricanes, and three major hurricanes, with an Accumulated Cyclone Energy (ACE) index of between 66 and 103 units. '''Pre-season outlooks The first forecast for the year was released by TSR on December 7, 2017, predicting a slightly above-average season in 2018, with a total of 15 named storms, 7 hurricanes, and 3 major hurricanes. On April 5, 2018, CSU released their forecast predicting a slightly above-average season with 14 named storms, 7 hurricanes, and 3 major hurricanes. In contrast, TSR released their second forecast on the same day, and called for a slightly-below average hurricane season, predicting 12 named storms, 6 hurricanes and 2 major hurricanes, due to recent anomalous cooling in the far northern and tropical Atlantic. Several days later, on April 16, the North Carolina State University released their prediction, calling for a well above-average season, with 14–15 named storms, 7–11 hurricanes, and 3–5 major hurricanes. On April 19, The Weather Company released their first forecasts, calling for 2018 to be a near-average season, with a total of 13 named storms, 7 hurricanes, and 2 major hurricanes. On May 25, NOAA released their prediction, citing a 40% chance of a below-average season due to cooler-than-average sea surface temperatures in the tropical Atlantic. On May 30, TSR revised its expected ACE index amount to 70 units. Mid-season outlooks The United Kingdom Met Office (UKMO) released its forecast of a very slightly above-average season, predicting 13 named storms, with a 70% chance that the number would be in the range between 11 and 14, 6 hurricanes, with a 60% chance that the number would be in the range between 4 and 7. It also predicted an ACE index of 112 units, slightly above the defined average ACE index of 103. On the same day, CSU revised their predictions, lowering their numbers of named storms, hurricanes, and major hurricanes due to below-average sea surface temperatures in the tropical Atlantic. TSR also revised their predictions to include Tropical Storm Alberto. On June 20, NCSU revised their predictions downward to 13 named storms, 7 hurricanes, and 3 major hurricanes for the same reason as CSU. Seasonal summary ImageSize = width:800 height:215 PlotArea = top:10 bottom:80 right:20 left:20 Legend = columns:3 left:30 top:58 columnwidth:270 AlignBars = early DateFormat = dd/mm/yyyy Period = from:01/05/2018 till:30/11/2018 TimeAxis = orientation:horizontal ScaleMinor = grid:black unit:month increment:1 start:01/05/2018 Colors = id:canvas value:gray(0.88) id:GP value:red id:TD value:rgb(0.38,0.73,1) legend:Tropical_Depression_=_≤39_mph_(≤62_km/h) id:TS value:rgb(0,0.98,0.96) legend:Tropical_Storm_=_39–73_mph_(63–117_km/h) id:C1 value:rgb(1,1,0.80) legend:Category_1_=_74–95_mph_(118–153_km/h) id:C2 value:rgb(1,0.91,0.46) legend:Category_2_=_96–110_mph_(154–177_km/h) id:C3 value:rgb(1,0.76,0.25) legend:Category_3_=_111–129_mph_(178–208_km/h) id:C4 value:rgb(1,0.56,0.13) legend:Category_4_=_130–156_mph_(209–251_km/h) id:C5 value:rgb(1,0.38,0.38) legend:Category_5_=_≥157_mph_(≥252_km/h) Backgroundcolors = canvas:canvas BarData = barset:Hurricane bar:Month PlotData= barset:Hurricane width:10 align:left fontsize:S shift:(4,-4) anchor:till from:27/05/2018 till:30/05/2018 color:TS text:"Alberto (TS)" from:28/06/2018 till:01/07/2018 color:TS text:"Beryl (TS)" from:09/07/2018 till:14/07/2018 color:TS text:"Chris (TS)" from:26/07/2018 till:01/08/2018 color:C1 text:"Debby (C1)" from:04/08/2018 till:06/08/2018 color:TS text:"Ernesto (TS)" from:12/08/2018 till:19/08/2018 color:C2 text:"Florence (C2)" from:22/08/2018 till:02/09/2018 color:C4 text:"Gordon (C4)" from:30/08/2018 till:07/09/2018 color:C2 text:"Helene (C2)" barset:break from:02/09/2018 till:04/09/2018 color:TD text:"Nine (TD)" from:05/09/2018 till:21/09/2018 color:C4 text:"Isaac (C4)" from:10/09/2018 till:11/09/2018 color:TS text:"Joyce (TS)" from:15/09/2018 till:17/09/2018 color:TS barset:break barset:skip barset:skip barset:skip from:20/09/2018 till:28/09/2018 color:C3 text:"Kirk (C3)" from:23/09/2018 till:02/10/2018 color:C3 text:"Leslie (C3)" from:05/10/2018 till:07/10/2018 color:TS text:"Michael (TS)" from:19/10/2018 till:23/10/2018 color:C1 text:"Nadine (C1)" from:11/11/2018 till:13/11/2018 color:TS text:"Oscar (TS)" bar:Month width:5 align:center fontsize:S shift:(0,-20) anchor:middle color:canvas from:01/05/2018 till:01/06/2018 text:May from:01/06/2018 till:01/07/2018 text:June from:01/07/2018 till:01/08/2018 text:July from:01/08/2018 till:01/09/2018 text:August from:01/09/2018 till:01/10/2018 text:September from:01/10/2018 till:01/11/2018 text:October from:01/11/2018 till:30/11/2018 text:November TextData = pos:(570,30) text:"(From the" pos:(618,30) text:"Saffir–Simpson hurricane wind scale)" The Atlantic hurricane season officially began on June 1, 2018, and was much less active than its hyperactive predecessor. The first storm, Tropical Storm Alberto, developed on May 31, while the final system, Tropical Storm Oscar, became a post-tropical cyclone on November 13. Sea surface temperatures in the tropical Atlantic were cooler than normal this year, which was expected to limit activity. However, the season featured above average activity, with 15 named storms, 8 hurricanes, and 4 major hurricanes forming. Several factors may have contributed to the unexpected high activity. The African monsoon was much more active than normal during 2018, which resulted in enhanced moisture levels across the tropical Atlantic. The subtropical regions were much warmer than normal, and wind shear was weaker than normal across the Atlantic basin. The tropical cyclones of this season caused about $35.98 billion in damages and 574 fatalities. The Atlantic hurricane season officially ended on November 30, 2018. Systems Tropical Storm Alberto The NHC began monitoring the potential for tropical cyclone formation in the Gulf of Mexico on May 21. A broad area of low pressure formed over the northwestern Caribbean Sea on May 24 and slowly organized. By May 26, the system was producing gale-force winds but lacked a well-defined center. Thus, the NHC began issuing advisories on a potential tropical cyclone at 12:00 UTC. A reconnaissance aircraft investigating the system at 06:00 UTC the following day was able to pinpoint a well-developed center of circulation, indicating the formation of Tropical Storm Alberto. Despite the presence of moderatley strong westerly wind shear, which displaced much of the deep convection to the east of the center, the cyclone managed to reach peak winds of 50 mph (85 km/h) before making landfall near Apalachicola, Florida on May 29. Alberto quickly weakened as it moved inland, and it transitioned to a post-tropical cyclone at 06:00 UTC the following day. As Alberto approached the Florida peninsula, governor Rick Scott declared a state of emergency for 27 counties to ensure that residents were prepared in advance for the storm's arrival. Heavy rainfall produced by the storm caused widespread flooding in several counties on and east of the Florida Panhandle. One indirect fatality occurred as a result of an automobile accident on Interstate 10. Total damages from Alberto are estimated at US$20 million. Tropical Storm Beryl On June 20, the NHC began monitoring a tropical wave that emerged off the coast of Africa. The wave drifted across the Atlantic without organizing due to unfavorable conditions. However, the wave began to steadily organize while over the Bahamas, resulting in the NHC designated the disturbance as Potential Tropical Cyclone Two at 18:00 UTC on June 27. A reconnaissance aircraft investigating the system at 06:00 UTC the following day confirmed the presence of a well-defined center, prompting the NHC to designate the system as Tropical Depression Two. Twelve hours later, the depression strengthened into Tropical Storm Beryl. Further strengthening ensued as banding features became evident. As it approached the coast of Florida, Beryl intensified further to reach peak winds of 65 mph (100 km/h). The storm made landfall near Panama City, Florida early on June 30. The cyclone slowly weakened as it moved inland and began to lose tropical characteristics. Beryl weakened to a tropical depression early on July 1 before transitioning to a post-tropical cyclone at 18:00 UTC. In preparation for the storm's arrival, Florida Governor Rick Scott declared a state of emergency for 53 counties, including areas that had been affected by Tropical Storm Alberto weeks earlier. Widespread flooding occurred throughout the state, causing two fatalities. An EF0 tornado spawned by the storm's rainbands damaged a few mobile homes in Marion County. Another brief tornado was reported, but caused no damage. Overall damages from Beryl totaled US$45 million. Tropical Storm Chris The NHC began monitoring a strong tropical wave located west of Cape Verde on July 5 for tropical cyclone development. Slow organization occurred as the wave moved across the Atlantic Ocean. Clusters of thunderstorms coalesced into a well-defined center of circulation on July 9, and at 12:00 UTC that day the disturbance was classified as Tropical Storm Chris. Continued organization occurred as Chris entered a more favorable environment, and the storm steadily strengthened as it neared the Lesser Antilles. By July 12, Chris was expected to strengthen into a hurricane amidst favorable conditions in its path, but the slow-moving storm failed to do so, peaking with sustained winds of 70 mph (110 km/h), just shy of hurricane intensity. At 20:00 UTC that day, Chris made landfall on the island of Martinique at peak intensity. Due to moderate wind shear over the Caribbean Sea, Chris began weakening shortly after making landfall. The storm turned northwest and weakened to a tropical depression on July 13. The following day, shortly after making a second landfall in Hispaniola, Chris degenerated into a remnant low and continued northwestward before completely dissipating on July 16. In the Lesser Antilles, tropical storm and hurricane watches and warnings were issued ahead of the storm. Torrential rainfall produced by Chris caused severe flooding and mudslides across the Lesser Antilles, mainly in Dominica, where US$85 million in damages and 7 fatalities were caused. 5 additional fatalities were reported, 2 in Martinique and 3 in Saint Lucia. Overall damages from Chris are estimated at US$120 million. Hurricane Debby A tropical wave moved off the coast of Africa on July 19, with the NHC introducing the wave as a potential contender for tropical cyclone formation the following day. The wave slowly organized as it tracked west-northwest through the tropical Atlantic. At 18:00 UTC on July 26, the disturbance developed into a tropical depression while located north of Puerto Rico. Organization continued as the depression tracked slowly northwest, and it strengthened into Tropical Storm Debby early on July 27. At 18:00 UTC on July 30, Debby strengthened into a hurricane, the first of the season. Accelerating northeast, Debby peaked with maximum sustained winds of 80 mph (130 km/h) at 22:00 UTC as it passed west of Bermuda. Shortly after leaving the warm waters of the Gulf Stream on July 31, Debby weakened to a tropical storm and began to rapidly weaken over cooler waters. The storm weakened to a tropical depression on August 1 shortly before becoming a post-tropical low at 06:00 UTC. Due to the threat posed by the hurricane, a hurricane watch was issued for Bermuda on July 30, although Debby ended up passing west of the island with little impact. Strong rip currents produced by the hurricane caused two drownings in the United States, one in the Outer Banks of North Carolina and another in Rehoboth Beach, Delaware. Tropical Storm Ernesto A trough of low pressure formed over the central Atlantic on August 2. Gradual organization ensued as the system entered a more conducive environment, and it became a tropical depression late on August 4. At 12:00 UTC the following day, the depression strengthened into Tropical Storm Ernesto. Citing favorable conditions ahead of the storm, the NHC predicted steady strengthening into a strong tropical storm or a minimal hurricane. However, Ernesto strengthened little, and instead peaked with winds of 50 mph (85 km/h) and began weakening shortly afterward, possibly due to dry air entrainment. Ernesto weakened to a tropical depression on August 6 as it continued northwestward, and by 12:00 UTC it lacked a closed circulation and was declared a remnant low. The remnants of Ernesto later contributed to the formation of Hurricane Hector in the East Pacific. Hurricane Florence Early on August 8, the NHC began tracking a tropical wave and its associated convection near Cape Verde. The wave tracked northwestward into the subtropics with little organization. As the wave reentered warmer waters, convective activity and organization increased, resulting in the formation of a tropical depression at 12:00 UTC on August 12. The depression continued to strengthen and organize, becoming Tropical Storm Florence at 00:00 UTC the following day. Low wind shear and warm water temperatures allowed Florence to organize and strengthen, resulting in the NHC upgrading it to a hurricane early on August 14. Strengthening continued as Florence turned southwestward around a subtropical ridge, and the hurricane briefly reached Category 2 strength late on August 15 before weakening. Interaction with another low pressure system to its southwest caused Florence to turn northward. After moving over an area of above-average sea surface temperatures, Florence restrengthened and reached its peak intensity with sustained winds of 105 mph (165 km/h) early on August 17. However, the hurricane began steadily weakening shortly afterward as it entered an area of increasingly colder sea surface temperatures and stronger wind shear. Florence fell below hurricane intensity on August 19 and became a post-tropical cyclone at 18:00 UTC. Hurricane Gordon Hurricane Helene Tropical Depression Nine Early on August 31, the NHC began tracking a weak and disorganized tropical wave that emerged off the coast of Africa. Although the wave lacked convective activity, conditions in its path appeared favorable for gradual organization. At 18:00 UTC on September 2, as the wave tracked west-northwest, it organized into a tropical depression. Citing warm sea surface temperatures and low wind shear, the NHC expected the depression to strengthen into a tropical storm. Unexpectedly, and possibly due to dry air entrainment, the depression failed to intensify and began weakening on September 3. By 06:00 UTC on September 4, the depression became devoid of convection, and it degenerated into a remnant low. Hurricane Isaac Tropical Storm Joyce Hurricane Kirk Hurricane Leslie Tropical Storm Michael Hurricane Nadine On October 17, a cold-core low formed at the end of a decaying cold front and drifted into the Gulf Stream. Due to warm sea surface temperatures and weak wind shear, the low began to acquire subtropical characteristics. On October 19, the NHC classified the low as a subtropical depression after a reconnaissance flight confirmed the presence of deep convection displaced from the system's center. At 12:00 UTC the following day, the depression strengthened into Subtropical Storm Nadine. Deep convection continued to organize near the center of the system, and Nadine transitioned to a tropical storm at 00:00 UTC the following day as it moved northeastward through the Gulf Stream. Steady strengthening followed, resulting in Nadine strengthening into a hurricane at 06:00 UTC on October 21. Intensification continued as Nadine moved over the warm waters of the Gulf Stream, and it reached its peak intensity on October 22 with windsof 90 mph (150 km/h). Shortly after moving over colder waters, Nadine weakened and became a hurricane-force post-tropical cyclone shortly before passing over Newfoundland. As an extratropical cyclone, Nadine brought strong winds and showers to the Canadian province of Newfoundland and Labrador. The strong winds downed trees and power lines, although overall damages were minimal. Tropical Storm Oscar Late on November 9, the NHC began monitoring an area of low pressure that had developed at the end of a cold front over the Central Atlantic. As the low drifted northeast it detached from the frontal system and began to acquire tropical characteristics. By 18:00 UTC on November 11, the low acquired enough tropical characteristics to be classified as Tropical Depression Sixteen. Twelve hours later, the depression strengthened into Tropical Storm Oscar. Despite the presence of unfavorable upper-level winds and strong wind shear, Oscar peaked with maximum sustained winds of 45 mph (75 km/h) on November 12 before it began to weaken. Early the following day, Oscar weakened to a tropical depression before degenerating into a post-tropical low and merging with a frontal system a few hours later. Storm names The following list of names were used for named storms that form in the North Atlantic in 2018. The names not retired from this list will be used again in the 2024 season. This is the same list used in the 2012 season, with the exception of the name Sara, which replaced Sandy. 'Retirement' On April 2, 2019, at the 40th session of the RA IV hurricane committee, the World Meteorological Association retired the names Gordon and Leslie from its rotating name lists due to the deaths and damage they caused, and they will not be used again for another Atlantic hurricane. They were replaced with Gary and Lucy for the 2024 season. Season effects This is a table of all the storms that have formed in the 2018 Atlantic hurricane season. It includes their duration, names, landfall(s), denoted in parentheses, damages, and death totals. Deaths in parentheses are additional and indirect (an example of an indirect death would be a traffic accident), but were still related to that storm. Damage and deaths include totals while the storm was extratropical, a tropical wave, or a low, and all the damage figures are in 2018 USD. Potential tropical cyclones are not included in this table. Category:2018 Atlantic hurricane season (Cooper) Category:Atlantic hurricane seasons Category:Above-average seasons Category:ENSO Neutral years